Book stack construction



R. C. WALKER BOOK STACK CONSTRUCTION June' 4, 1935.

Filed April 5, 1933 3 Sheets-Sheet 2 a mm 5 3 mm fikfi ghm n w 7 v June4, 1935. R. c. WALKER BOOK STACK CONSTRUCTION Filed April 5, 1933 3Sheets-Sheet 3 Patented June 4, 1935 UNITED STATES BOOK STACKCONSTRUCTION Robert C. Walker, Scarsdale, N. Y., assignor to RemingtonRand Inc., Buffalo, N. Y.

Application April 5, 1933, Serial No. 664,576

11 Claims.

This invention relates to improvements in a book stack construction.

This book stack invention provides a plurality of stack column membersof substantially uniform size and dimension for the erection of a bookstack in a progressive manner beginning at the foundation and erectingone floor at a time on the upper ends of each set of column memberswhich have a length substantially equal to the distance between floorswith a floor structure of unit type. The floor structure has a pluralityof sheet metal sections formed for stress distributing cooperation forthe purpose of providing a rigid floor structure connecting the columnsin the book stack in such a manner that the columns will be held inrigid assembled relation. The sheet metal floor structure cooperateswith the columns to carry and distribute the load applied thereto. Theinvention further provides a floor structure having the sections insubstantially unit form, and of such a character, that they can bemadein standard sizes and set up at any desired point with uniformlyconstructed column members formed for interengaging cooperation. withthe floor sections.

The invention provides floor structures having uniformly smooth ceilingsurfaces between the rows of columns in all directions in order thathead room in the stack aisles is not obstructed in any way. In obtainingthis result the floor structure comprises spaced parallel plate membersconnected by intermediate angular sectional portions that are rigidlyassembled with the spaced parallel plate members to provide the rigidfloor structure having the necessary load carrying and distributingqualities.

This floor structure will also provide for the housing of electricalcables or other electrical circuit wires that it may be desired to havein the stack structure for lighting or other types of equipment.

The invention provides a floor structure having overlapping,interfitting and interlocking joint connections between floor sectionsso arranged that the joint between each section of sheet metal in thefloor structure will occur at a different point in the floor and therebydistribute the joints between sections in a manner that will provide forthe efficient assembly of the floor sections at the same time securing amaximum strength in the assembled structure. 1

The invention further provides for a special wall structure cooperatingwith the stack construction to provide either a permanent or temporarystack and building structure in which the walls for the building will beattached to and substantially carried and supported by the stack.

In the drawings;

Fig. 1 shows in perspective several floor sections in assembled relationon the upper ends of a plurality of stack column members, only asufiicient number of the floor sections and columns being illustrated toshow clearly how a stack'incorporating the present invention is con-'-structed.

Fig. 2 is a vertical cross section through one of the column members anda floor section supported thereby showing the complete floor structureand the manner in which it is assembled with the stack column members.

Fig. 3 is a vertical cross section taken on line' 3-3 of Fig. 2. I

Fig. 4 illustrates in perspective, the structure of the sheet metalfloor sections and particularly the manner of arranging the overlappingends to secure two adjacent sections in assembled relation to provide arigid floor structure, the floor sections being illustrated indisassembled and separated relation.

Fig. 5 is a vertical cross section through a stack column member and afloor section assembled therewith also showing the outer wall structureof this invention assembled with the stack, the wall structure being ofa substantially temporary type.

Fig. 6 shows a vertical cross section of a stack column member'andassembled floor structure with a slightly difi'erent type of wallstructure to form the outer wall of the building for the stack.

Fig. 7 is a vertical section through a column and floor section showinga modified construction.

The book stack construction provided by this invention uses foundationplates i that may be made of sheet metal and are arranged in coplanarrelation on the foundation of any building or building floor that isconstructed to carry the load of the stack. The usual unevenness of thefloors and foundations of a building presents a problem in the buildingof a book stack from uniform sized partsbecause of the difliculty inlining up the parts to support the book shelves and carry the load. 7,

The use of the foundation plates I, therefore, provides a means forconstructing a book stack where uniform-sized parts can be employed. Thefoundation structure of the building is suitably modified where desired,by building up or cutting down, so that all of the foundation plates maybe arranged in their proper spaced relation in rows both longitudinallyand transversely of the book stack structure or the building structure,and levelled so that they will be in the same plane, or as stated above,in coplanar relation.-

The positioning of the foundation plates I determines the positioning ofall of the stack columnsin the stack structure. These foundation platesare suitably anchored to the foundation of the building structure by lagscrews or the like extending through holes in the plate. The cornerportions of these foundation plates are provided with upwardly extendingbendable tongues 2, see Figs. 5 and 6, that extend through openings inthe base plate 3 onthe lower ends of the stack column members 4. Theconstruc-v tion of the foundation plates I, and the stack column members4 with the base ,plates 3 and top plates 5 on opposite ends, is fullydescribed in co-pending application, bearing a serial number with whichthe number of this application is consecutive, and filed-on even dateherewith.

The column members 4 are provided with a pluralityof slots 6 arranged inrows so that ad jacent columns will receive the opposite ends of bookshelving and the hook connections on the end members of the selves willdetachably engage in these slots in order to support the shelves on thestack column members. The top plates 5 are provided with upwardlyextending tongues l as shown in Figs. 2 and 5.

In the erection of a stack according to this invention, the foundationplates are first placed in position, then a set of stack column members4 are mounted on the foundation plates and the tongues 2 turneddownwardly in order to firmly secure the stack column members to thefoundation plates. Then the structure is ready for the application ofthe first floor structure.

Before applying the floor structure, a bearing plate 8 is mounted on theupper end of each of the column members 4. The bearing plates 8, asshown in the drawings, are of rectangular form and are larger than topplates 5 on the column members. These bearing plates are provided withopenings 9 positioned to receive upwardly extending tongues 'l on topplates 5 and in this way the bearing plates are interengaged with topplates 5, and held in position on the upper ends of column members 4.These bearing plates form a means ofdistributing and equalizing the loadapplied to column members 4 bythe stack structure above.

After bearing plates -8 are appliedto the column members, the firstfloor sections are then placed in position and assembled. Two difierentkinds of floor sections are used in the structure of the floor as shownin the drawings, and include the floor-sections H} and the stripsections generally indicated at 11, although the floor may beconstructed with the use of other types of floor sections where they mayall be of one standard size.

The strip sections H extend longitudinally or transversely of the stackin one direction only, and are interconnected at their ends. They aremounted on the upper ends of the column members in each row and serve toconnect all of the columns in each row, while the floor sections it areinterlocked with the'edge portions of strip sections 1 I to complete thefloor structure.

Each strip section H includes a relatively narrow floor plate 42, anintermediate corrugated strip 13 and a'ceiling plate 14. The plates l2,I3 and [4 are of substantially equal length, but they are offsetlongitudinally, in order that the ends will terminate in overlapping orstepped relation so as to provide an overlapping structure at one end ofeach strip section that is the complement of the overlapping section atthe opposite end thereof. In this way the ends of two adjacent stripsections H will be adapted for complementary overlapping engagement witheach other in a manner to be described. The floor plate I2 is in theform of a narrow elongated flat plate. The intermediate corrugatedsection 53 has a series of sections 15 arranged in coplanar relation andseparated from each other by channel sections it which projectto oneside of the sections l5. These channel sections it are formed from thesame sheet of material with sections id to provide the corrugatedintermediate member !3. The sections !5 are suitably welded at intervalsto the contacting portions of floor plates l2 by spot welding, plugwelding or any other suitable form of connection that will provide asmooth floor surface on the top face of the floor plates.

As shown in Figs. 1 and 4 floor plates l2 have the ends 5'! oiiset fromthe ends it of corrugated sections i3, to provide an exposed portion ofsections i5 beyond the end ll of each floor plate l2. This occurs at oneend of the strip sections I! while at the opposite end a correspondingportion of fioor plate I2 overhangs the end of intermediate section l3to such an extent that it will overlie the intermediate section 43 ofanother strip section l i so as to abut the end I! of floor plate l2 onsuch other strip section. The ceiling plate 14 projects beyond theend H}of intermediate section l3, as indicated at 19 in Fig. l, and theopposite end terminates short of the opposite end of the intermediatesection a distance equal to the distance between the ends l8 and is. Inthis way the ends of the strip sections are complementary to each other.

When two of these strip sections are assembled together the ends areregistered in abutting relation, that is, the ends of the respectivesections l2, l3 and I4 abut in end to end relation and as a resultportions of the sections l2, l3 and I4, on two adjacent sections overlapeach other. The overlapping portions are spot welded, plug welded orotherwise secured together to form a unitary structure.

The ends of each strip section terminate over one of the bearing plates8 in the manner illustrated in Figs. 1, 3 and 4, and each ceiling plateM is provided with openings 20 positioned to receive tongues l on topplates 5. This provides an interengagement between the strip sectionsand the column members, so that in the assembled relation of the stripsections on the column members, the ends of the column members areuniformly spaced apart and interlocked with the strip sections toprovide a rigid stack structure in assembled relation. The ends oftongues may be bent down on top of the ceiling plate to furtherinterlock the column members with the strip sec tions.

Each strip section has the intermediate corrugated section i3 formed sothat the side edges terminate in channel portions 53. ceiling plate i4is formed along the side edges to provide upwardly extending angularflanges on apps-- site sides engaging and secured to the outside ofchannel members IS. The floor plates 52 are of less width than thesections 13 and M as illustrated in the drawings, having the side edgesterminating intermediate channel portions 5'5 and over portions I5 ofthe intermediate section.

Floor sections iii are constructed to havesuband to extend between andinterlock with the strip sections connecting column members in adjacentrows in the manner illustrated in Fig. 1. Each floor section comprises afloor plate 22 having the side edges abutting the side edges of floorplates I2 and overlying portions #5 of the intermediate section 53 ofstrip member H to which they are suitably secured by plug Welding or inany other suitable manner.

Each floor section I!) includes an intermediate corrugated section 23having a plurality of channel portions 2 2 formed at spaced intervalstherein. The sections 23 are formed from a single piece of sheetmaterial as illustrated and the channel portions 24 are of similar sizeand dimension to channel portions IS. The side edges of the intermediatesection 23 terminate in channel portions 24 that are formed of a size tointerfit in channel portions 6 at the side edges of strip sections H inthe manner illustrated in Figs. 1 and 2 to provide an interlocking jointbetween floor sections It and strip sections H.

Each floor section it) is provided with a ceiling plate 25 havinginwardly extending angular flanges 25 at the side edges arranged inspaced parallel relation to the channel portions 24 at the side edges ofintermediate section 23 so as to provide a groove for receiving theflange 25 on the ceiling plate and the connected portion of channel itof intermediate section l3. This provides an interlocking connectionbetween the side edges of the floor sections and adjacent strip sectionsil.

The ends of the floor section iii are offset to provide complementaryportions at opposite ends of each floor section. At one end of eachfloor section ill the intermediate section 23 terminates beyond the endof floor plate 22 as shown in Fig. l and ceiling plate 25 has one endterminating beyond the end of intermediate section 23.

When floor sections 56 are assembled with strip sections H, the end ofeach floor plate 22 is arranged to terminate in coincident relation withthe ends of corrugated intermediate section l3 of strip sections ll asshown in Fig. 1. The end of intermediate section 23 terminatescoincident to the end of ceiling plate M of strip sections ll whileceiling plate 25 has the end terminating in offset relation thereto. I 7

Floor plate 22, intermediate section 23, and ceiling plate 25 are allrigidly welded together at a plurality of points throughout their widthand length to provide a rigid floor construction, the plates 22 and 25cooperating with intermediate section 23 formed with channel portions 24so that the plates 22 and 25 are spaced apart while intermediate section23 has stress distributing cooperation therewith. Floo-r plates 22 arewelded at a plurality of points along the side edges to strip sections Hand the overlapping complementary portions of each floor section Ii! ininterengaged relation are welded together to form a continuous rigidi'loor structure in which the ends of each floor plate 22 of eachsection abut the ends of floor plate 22 of each adjacent section and theends of the corrugated intermediate sections 23 and ceiling plates 25likewise abut in end to end relation with the corresponding portions ofadjacent floor sections.

After a set of stack columns are erected on the foundation plates, aseries of floor sections and strip sections ill and H respectively areassembled together in the manner described above on the tops of thebearing plates to provide a complete floor on the upper ends of thefirst set of column members. After this structure is completelyassembled, the next set of columns is then erected to support the secondfloor in the book stack. In order to provide for the proper positioningof the second set of stack column members on the assembled floorstructure, each floor plate l2 has a positioning plate 27 secured on oneend in the manner shown in Figs. 1 and by welding or in any othersuitable manner. These plates 21 are located on floor plates l2 in a.position so that they will overlie the top plates 5 on the columnmembers below in coincident spaced parallel relation. These positioningplates are constructed in a manner similar to foundation plates I. Theplates 2! are provided adjacent the corner portions with upwardlyextending tongues 28 for interengagement in the holes in the bottomplates 5 on'column members 4'that are erected on top of the assembledfloor structure to support the next floor above. When these columnmembers are in position in the manner shown in Figs. 5 and 6, they willbe properly centered in end to end relation over the first. set ofcolumn members so that the slots 6 will be spaced apart the properdistance to receive standard length shelving. The tongues 28 may be bentdownwardly on top of the bottom plate of the column members seatedthereon so as to hold the column members in rigid assembled relationtherewith.

In the assembly of the floor sections l and l I on the upper ends ofcolumn members 4, provision may be made for load transmission throughthe floor between the'ends of upper column members and column membersbelow the floor, by filling the spaces between adjacent corrugations ofthe intermediate corrugated sections i3 where they overlie bearingplates 8 with concrete or similar material as indicated at 30 in Figs. 2and 3. In this way the transmission of the load from one set of columnmembers to a set below, is obtained without applying unnecessary loadsor stresses on the floor structure.

The succeeding floors above the first floor are arranged on the upperends of the column mem bers in the same manner as above described, onefloor being constructed after another in progressive relation upwardlyuntil the entire stack structure is completed. All of the parts arewelded together, in the manner described, to provide a rigid stackconstruction having the floor and strip sections l0 and i! cooperatingto provide a rigid integral floor structure providing means for iholding column members 4 in assembled relation to form the book stack,and carry and distribute the load. This structure will also provideunobstructed head room along the ceiling surfaces of the aisles of thestack after the shelves are put in place by interlocking them in slots 6in the column members.

I Where the stack is erected in a building, it is to be understood thatthe foundation plates 1 will be placed in position and the stack erectedin the manner described, independent of the building wall and so thatthe main stack structure including the series of columns and floorsections assembled together will be substantially independent of thebuilding and will fill the entire space provided for the structure. Fig.6 illustrates a construction of this character having the building wall3! shown in spaced relation to the outer row of column members 4. Due tovariations in the structure of the building wall from the structure ofthe stack that occur in such constructions, the stack construction willbe built so that wall engaging floor sections 32 will be constructed tohave the proper dimension to fill the space between the outer edges ofassembled strip sections I I and floor sections II) of the floorstructure and the wall. The wall engaging floor sections 32 will havefloor plates 33, intermediate corrugated sections 34, and ceiling plates35. These parts, 33, 34 and 35, will be formed at the side engaging withthe strip sections II to interlock with the interlocking edge portionsthereof in the same manner that floor sections I0 interlock therewith,along the side edges. Where wall engaging floor sections 32 are at theends of floor sections I9 or strip sections II, the ends will terminatein offset overlapping relation to form complementary parts to the endsof floor and strip sections 58 and I i, in a manner that will be clearlyunderstood from the above description of these parts. In other words,the portions of all of the wall engaging floor sections 32 that surroundthe main stack structure in a building will have complementary portionsto interlock with adjacent floor and strip sections to provide acomplete floor structure in the. building. V

The outer edges of Wall engaging sections 32 carry a Wall engaging plate36 having a lateral flange 3'! suitably secured to the outer edge of thesection under ceiling plate 35. Suitable anchor members 38' are extendedthrough openings in the wall engaging plate 36 and embedded in wall 3|to firmly attach and anchor the floors of the book stack structure tothe walls of the building. These wall engaging sections 32 areconstructed to correspond with the floor and strip sections It and I Iat adjacent edges so that a plurality of wall sections 32 have theiradjacent edges provided with complementary interengageable portions thesame as floor sections ID and I I. It is not believed necessary todescribe these in View of the above description showing how adjacentstrip sections II and floor sections I0 are interengaged with each otherand with adjacent strip and floor sections at the ends and side edges.

The spaces between channels 24 of floor sections l0 may be used forelectrical conduits or other wiring for the book stack that may benecessary, the ceiling plates 25 being drilled to seat the connectionboxes for the electric circuit at desired intervals.

The book stack structure may be built according to this invention sothat the stack structure provides a combined building structure attachedto and constructed in conjunction therewith. Such a type of constructionis illustrated in Fig. 5 having wall engaging and supporting floorsections 39 constructed and assembled in the same manner as wallengaging sections 32.

To construct the walls of a building with this type of construction,sheet metal plates 40 are erected around the outside of the stack toform inner walls for the stack building, these sheet metal plates beingbolted. or otherwise suitably attached to wall engaging portions M offloor sections 39. Outside of the inner wall plates 40 is arranged aseries of insulating slabs 42. Suitable forms of well known compositionboard may be used for this purpose, and are known to provide efficientinsulation for building structures. These are bolted to the wallengaging plates M with the same bolts that secure inner wall plates 40thereto as clearly shown in Fig. 5 and indicated at 43. A series ofbrackets 44 are mounted on the outside of the insulating slabs 42 andmay be bolted thereto and to the inner wall members 46 so as to providea rigid mounting for the brackets 44. Expanded metal diagrammaticallyindicated at 45 in Fig. 5 is then attached to these brackets 44 and asuitable coating of cement, pebble dash, or other type of outsidefinishing material indicated at 46 is then applied to the expanded metalor other mesh structure so as to form an outside wall structure for thestack building. Of course, windows may be inserted in this structure toprovide for the admission of light and air to the stack structure atdesired points, and the manner of constructing and mounting the windowsin the wall can be done according to any well known method.

This type of construction as shown in Fig. 5 provides a stack buildingwherein the stack structure is rigidly assembled together and supportsboth the walls and roof of the building. The roof is applied to floorsections mounted on the upper ends of the uppermost column members byputting suitable roofing material over the floor sections. The loads onthis structure are carried by the stack structure including the columnmembers, the column members cooperating with the floor structure tosupport the walls for the building. The wall structure also cooperateswith the stack structure in carrying and distributing loads to aconsiderable extent and provides a building structure that can bedismantled whenever removal of the stack is desired. This constructiontherefore, provides What may be termed a temporary form of stackstructure that has the strength and cooperation between the differentparts that is necessary to carry all the load applied on the book stackand may be used for a permanent building structure as long as desired,that is economical to construct.

In some cases it may be desirable to seat the base plate of an uppercolumn member in substantial adjacent and interlocked relation with thetop plate of the column member below. This may be done as shown in Fig.'7 by cutting an opening 50 in the floor plate I2 and intermediatesection I 3 in each strip section at the point where the positioningplate 21' is located and slightly larger than this plate in order toprovide for the entry of the base plate 3 on a column member having thesame size and shape as positioning plate 21.

With the structure shown in Fig. 7, the base plate 3 of the columnmember will extend through openings 50 and seat on the upper face ofceiling plate 14 in aligned relation over the column member below andwith the openings in the base plate receiving tongues 'I on the topplate of the column member below for accurately positioning the columnmember in aligned relation. These tongues may be bent over to firmlyitnerlock one column member with another and in order to provide afurther means of holding the column members in. assembled relation,interlocking with each other and with the floor structure, the openingsthrough the hole 52 may be filled with concrete as indicated at 5!, ifdesired. The struc ture shown in Fig. 7 still obtains full cooperationof the floor members with the column members in assembled relation toform a substantially rigid stack structure that will equalize anddistribute the loads supplied thereto between the fioor structure andthe column members and thereby provide a stack structure that can bemade of relatively light weight sheet material formed in such a mannerthat it will carry substantial loads.

The invention claimed is: 1. A library stack, comprising a plurality ofvertically spaced floors, each floor having a plurality of metal floorsections formed on the marginal portions for interfitting interlockingcooperation with adjacent marginal portions of adjacent floor sections,a plurality of stack column members extending between and supportingsaid floors and arranged in rows longitudinally and transversely, saidstack column members being in vertically aligned relation, load carryingmeans on the floors extending between the ends of aligned column memberson opposite sides thereof, and foundation plates mounted in horizontalcoplanar and predetermined spaced relation, said plates receiving andsupporting the lower ends of the lowermost column members and providinga base for supporting the library stack and predetermining stack columnposition.

2. A library stack, comprising a plurality of vertically spaced floors,each floor having a plurality of floor forming sections formed tooverlap and interlock at the marginal portions with similar sections toprovide a floor having smooth continuous floor and ceiling surfaces, aplurality of stack column members extending between adjacent floors andarranged in rows in spaced relation longitudinally and transversely outof alignment with the joints between floor sections, and meansdetachably interlocking the ends of said stack column members with saidfloors, the column members between difierent floors being in alignedrelation.

3. A library stack, comprising a plurality of floors spaced uniformlyapart, a plurality of stack column members of uniform size extendingbetween adjacent floors and supporting said floors, said column membersbeing arranged in rows longitudinally and transversely of the stack,column members between different floors being in aligned relation, eachfloor having a series of column connecting strip sections and floorsections, said column connecting strip sections connecting the columnmembers of each row in one direction together, said sections each beingformed with cooperating parts for interlocking the strips together ineach row, said floor sections extending between rows of columns and theconnecting strip portions and having cooperating parts on all of saidsections for interlocking the fioor sections together, and interlockingthe floor sections to the strip sections, whereby the assembled floorand strip sections cooperate to provide rigid floors for said stack,secure said column members thereto in assembled relation and provide acomplete substantially rigid book stack.

4. A library stack, comprising a plurality of floors spaced uniformlyapart, a plurality of stack column members extending between said floorsand arranged in rows longitudinally and transversely, the column membersbetween different floors being in aligned relation, said floorsincluding a floor structure having a plurality of connecting stripsections, and a plurality of floor sections, said strip sections beingin interengaged and interlocked relation in rows and connecting saidcolumn members together in rows in one direction, and said floorsections having interengaged interlocked connection in rows arrangedalternately with rows of strip sections, said rows of floor sectionshaving interengaged and interlocked connection at the side edges withsaid connecting strip sections, said floor and strip sections havingstress distributing coopermembers to provide a substantially rigid bookstack structure.

5. A library stack comprising a plurality of floors, a plurality ofstack columnmembers extending between and supporting said floors, saidcolumn members being in spaced relation in rows longitudinally andtransversely of said stack, column members between different floorsbeing in aligned relation, said floors comprising a floor structurehaving a plurality of floor sections, each floor section having spacedfloor and ceiling plate members and a plurality of connecting membersextending between and rigidly connecting said floor and ceiling platemembers having stress distributing cooperation therewith to providesubstantially rigid floor sections, each iioor section havingcooperating parts for interconnection with corresponding parts ofadjacent floor sections to provide a substantially rigid floor structurewith the respective floor and ceiling plate members of each section incoplanar relation.

6. A library stack, comprising a plurality of floors, a plurality ofstack column members extending between and supporting said floors, saidfloors comprising a plurality of floor sections, each section havingspaced parallel floor and ceiling plate members, and a plurality ofconnecting sections extending transversely between and rigidlyconnecting said fioor and ceiling plate members for stress distributingcooperation, each floor plate member having opposite ends offsetrelative to the ceiling plate member and connecting sections to provide,overlapping interconnecting end portions between adjacent floor sectionsin assembled relation, said floor and ceiling plate members and saidconnecting sections being formed at opposite sides of each floor sectionto engage in complementary portions of adjacent floor sections forinterlocking cooperation, whereby a substantially rigid floor structureis provided by a series of connected floor sections.

'7. A library stack, comprising a plurality of floors, a plurality ofstack colunm members extending between and supporting said floors, saidfloors comprising a plurality of floor sections, each section havingspaced parallel floor and ceiling plate members and a plurality oflaterally extending connecting members between and rigidly connectingsaid floor and ceiling plate members having stress distributigcooperation therewith to provide substantially rigid floor sections,each floor section having cooperating parts for interconnection withcorresponding parts of adjacent floor sections to provide asubstantially rigid floor structure with the respective floor andceiling plate members of each section in coplanar relation, andcooperating parts on said floor section and said stack column membersfor detachably connecting said stack column members to said floorstructure for stress distributing cooperation therewith to provide arigid stack structure.

8. A library stack, comprising a plurality of floors, each composed of aplurality of floor and ceiling plate members mounted in spaced parallelrelation, stress distributing members extending between said floor andceiling plate members and rigidly connecting said members in assembledrelation, a plurality of stack column members extending between thefloor plate members of one floor and the ceiling plate members of anadjacent floor next above, said stack column ceiling plate membersrigidly connecting said members in assembled relation and having stressdistributing cooperation therewith, each plate member havingcomplementary parts formed on the marginal portions thereof forinterlocking cooperation with the cooperating marginal portions ofadjacent similar plate members for interlocking a series offioorsections together in assembled floor forming relation with thefloor and ceiling plate members of each section arranged in coplanarrelation respectively.

10. A library stack, comprising a plurality of floors spaced uniformlyapart, each floor having a plurality of sections in coplanar relation,the marginal portions of each section being formed to overlap andinterfit in interlocked complementary relation with the margins of othersections, a plurality of stack column members extending between floorsarranged in unijorm spaced relation in longitudinally and transverselyextending rows, each column member having plates engaging the floor inthe zone of said marginal portions and engaging a plurality of floorsections, and parts on said floor sections and plates for interlockingsaid floor sections with said column members.

11. A reinforced sheet metal floor structure for library stacks,comprising a series of strip sections and floor sections, said stripsections being arranged in rows in one direction, each row being spacedapart a distance equal to the width of a floor section, said floorsections being arranged in rows between said rows of strip sections,said strip sections having cooperating complementary parts on the endsthereof for interengaging interlocking connection with adjacent stripsections, said floor sections having interlocking parts on the ends forconnecting each section to adjacent floor sections, and said strip andfloor sections having complementary interlocking parts for securing theside portions of said strip sections to the side portions of adjacentfloor sections to cooperate in forming a fioor structure havingsubstantially smooth floor and ceiling surfaces. 7

' ROBERT C. WALKER.

